Rotative driving coupler



June 8, 1954 w. J. MoRRlLL 2,680,559v

ROTATIVE DRIVING COUPLER Filed Nov. 2, 1949 2 Sheets-Sheet 1 June 8A, 1954 w, J, MoRRlLL 2,680,559

ROTATIVE DRIVING COUPLER Filed Nov. 2. 1949 2 Sheets-Sheet 2 Patented June 8, 1954 UNITED STATES PATENT OFFICE 2,680,559 ROTATIVE DRIVING COUPLER Wayne J. Morrill, Fort. Wayne, Ind. Application November 2, 1949, Serial No. 125,112

(Cl. B30-259) 2 Claims.

range of frequencies.

I have discovered that in an electric motor, the

According to the theory relating to my discovery, I have found that, when the frequency of a particular motor vibration beof noise frequencies tric motor having a slotted stator and a slotted rotor.

UD; the audible frequency range. When a motor is running at high or full speed, the resonant frequency caused by the slotted stator and slotted rotor is generally at a frequency higher than the frequencies of the audible range and thus is Gusts of wind hitting the fan blades Will slightly change the speed of rotation of the rotor, thus changing whine or howl resonated from the fan blades.

I have discovered that a principal type of motor` vibration which produces the noise is a rotational designed a driving coupling to eiect transfer of' iriving ymotion from the driving meinberor rotor Another object of invention is to use the fan blade hub as the end bell of an electric motor and resiliently mount the end bell or the fan hub on the rotor.

Another object of my invention is to provide the rotor with a surface and the end bell with a surface spaced from and facing the surface of established therein.

Other obj ects'and a fuller understanding of my had by'reierring to the fo11ovvclaims, taken in conjunction Figure 3 is a fragmentary cross-sectional Viewy oi a modiiicaton of my invention,- and Figure 4 is a fragmentary cross-sectional view of a second modification of my invention.

n Figure l l illustrate, as one of the practical uses of my invention, a Window fan support frame l supporting a motor H having an end bell constituting a fan blade hub I2, which carries fan blades i3. The motor l! has a rotor It rotatively mounted on a shaft l5. Since this shaft l5 may be supported by suitable supporting methods known in the art of mounting shafts in motors, I have not illustrated the exact method of mounting in my drawings. The rotor i4 is provided with bearings I6 separated by an oil felt pad I1, with the bearings providing an anti-friction mounting of the rotor i4 on the shaft iii. I have also provided the shaft I5 with an oil conduit hole i8 extending from the end of the shaft past one of the bearings i3 and outwardly to the oil felt pad l1. The bearings I3 may thus he oiled through the conduit hole i3, which opens on the end of the shaft I3. An oil cap t3 may be inserted into the rotor id to cover the end of the shaft l5 and prevent dirt entering the bearing l5 and the oil felt pad il. it is understood that other methods of lubrication and bearings may be used without departing from the spirit and scope of my invention.

rfhe resilient and vibration-isolating coupling of the end bell or hub i2 on the rotor ill is best illustrated in Figure 2 of the drawings. The rotor is a specific form of a driving member and may also be referred to as a rotative member. The hub or end bell is a specific form of a driven member and may also be referred to as a rotated member. The rotative member or rotor i4 and the rotated member or hub l2 are interengaged by a vibration isolating or resilient material 23, which frictionally engages the rotor and the hub and thereby effects transfer of driving motion. The vibration-isolating material 2d may be of any suitable material, such for example as rubber, which may be compressed axially of the rotor and put in shear to rotational vibration to isolate vibrations and thereby prevent transfer of noise-forming vibrations from the rotor ill to the hub l2 and thus to the resonated fan blades i3.

The rotor Ul has a surface 22 disposed in a plane transversely of the axis cf rotation of the rotor. An extension portion 23 extends outwardly from this surface 22 and is provided with an annular groove 2li at the outer snap ring. This extension portion 23 is described as having an extension surface 25 extending thereabout and between the surface 22 of the rotor Ui and the annular groove 23.

The end bell hub for supporting the fan blades i3, has a center support portion 2l', which encircles the extension portion surface 25. The surfaces on the opposite sides of the center support portion 21 are designated by the reference characters 23 and 29, with the surface 28 being spaced from and facing the surface 22 of the rotor le. An opening in the center support portion 2l' defines a cylindrical surface 3l?, which is spaced from and faces the extension surface 25 of the extension portion 23 of the rotor Hi. The vibration-isolating or resilient material 2! frictionally engages the surfaces of the rotor and the surfaces of the end bell or hub and thereby transmits rotational driving movement from the rotor to the hub.

l have found that the most practical way of using this vibration-isolating material 23 is to form the material into washers 32 and 33 and into a sleeve 3d. The washer 32 is inserted over the extension portion 23 and against the surface end thereof to receive a e' l2, which constitutes a fan blade i lil) 22 of the rotor. Similarly, the sleeve 34 is slipped over the extension portion 23 and frictionally engages the extension surface 25 of the rotor. The end bell or hub l2 may next be slipped onto the sleeve 32 and against the washer 32 with the surface 28 of the end bell engaging the washer 32 and thus facing the surface 22 of the rotor. The Washer extension portion 23 of the end bell i2. To hold these washers 32 and 33 and the sleeve 34, which operate as a unitary structure to form the vibration-isolating or resilient material 28, in frictional engagement with their respective surfaces, I have used a holding washer 35 and a snap ring 33. The holding washer 35 is forced on to the extension por.- tion 23 and compresses the washer 32 and 33 axially of the rotor. After the holding washer is forced on to the extension portion 23 past the annular groove 2t, the snap ring 36 is snapped into the annular groove 203. The snap ring 33 holds the holding washer 35 a predetermined distance from the surface 22 of the rotor, thus maintaining an axial compression on the vibrationisolating or resilient material 28 and thereby preventing wobble and eccentric rotation of the hub. The vibration-isolating or resilient material 20 operates in shear to the rotational vibration and prevents transfer of vibration from one member to the other member, in this instance from the rotor to the hub.

In Figure 3 of my drawings, I illustrate a modincation of my invention and my rotative device. In this instance, the hub or end bell l2 is provided with an annular sleeve 3S having an inernal surface 3e, spaced from and facing the extension surface 25 of the extension portion 23 of the rotor i3. A sleeve i3 of suitable vibrationisolating material frictionally engages the internal surface :le of the annular groove 38 and the extension surface 25. This resilient sleeve Ml may be bonded to the hub l2 and the rotor M or it may be forced between the sleeve 38 of the hub i2 and the extension portion 23 of the rotor lil. The sleeve 43 of resilient material effects the transfer of driving motion from the rotor to the hub or end bell and prevents the transfer of noiseforming vibrations from the rotor to the fan blades.

I have also discovered that the end bell l2 may be provided with a support sleeve 4l extending outwardly from one side thereof, as illustrated in Figure e of my drawings. The support sleeve di has an outer surface 42 extending thereabout, and has bearings 33 therein for bearinglyr supporting the end bell l2 of the shaft l5 in much the same manner described in connection with Figure 2 of my drawings. A rotor or driving member iii having an internal surface 45 is supported about this support sleeve @L The internal surface i5 of the driving member or rotor 44 is spaced from the outer surface l2 of the support sleeve di and faces the surface d2. A sleeve 46 of suitable vibration-isolating or resilient material frictionally engages and separates the surface fifi of the rotor 4@ from the surface 42 of the support sleeve l. This sleeve 33, as in the other embociments of my invention, transmits driving movement from the rotor to the support sleeve lli and thus to the fan blades carried thereby. the embodiments of my invention, l driving member and a driven member interengaged by a vibration-isolating oi resilient material. 1n each instance, one of thesr members is supported by the other member witl the vibration-isolating or resilient material separating the members from direct contact. The

of my invention as hereinafter claimed.

What is claimed is:

1. In an electric fan motor having a stator and a rotor with a substantially axial cylindrical tioned mounting and to provide an axial compression force on said resilient Washers to transresilient washers to transmit torque between said rotor and said fan hub.

References Cited in the file of this patent UNITED STATES PATENTS 

